This invention relates to a weft detaining device of a shuttleless loom, of the type wherein a weft yarn is detained by being wound a certain number of times around a drum prior to a weft picking, and more particularly to the drum type weft detaining device which is provided with a device for adjusting the length of the weft yarn detained around the drum which length corresponds to a weft yarn length required for each weft picking.
In connection with conventional drum type weft detaining devices of shuttleless loom, changing the weft yarn length required for each weft picking or the detained amount of the weft yarn has been accomplished by replacing a drum for detaining the weft yarn with another drum whose outer diameter is different from the former drum, otherwise by increasing or decreasing the number of outer diameter adjusting members to be mounted on the peripheral surface of the drum. However, such conventional weft detaining devices have encountered problems in which it is required to prepare many drums having different sizes or many outer diameter adjusting members. This is uneconomical, rendering the operation and maintenance of the weft detaining device difficult and complicated.